The majority of production from the district comes from quartz veins within faults and fractures. The north to northwestern trending veins is up to several kilometers long, dips steeply to the west and is 0.5 to 30 meters wide. Ore shoots up to several hundred meters in length, extends to at least 900 meters below the surface and is separated from other ore by 0.5 to 1 meter of barren quartz vein. Metal zoning occurs in some veins, with zinc and lead content generally decreasing with depth and copper increasing with depth. Three main systems of veins exist inside the district, represented by the veins Coyote, Segovedad Novedad and Coyote Seca Palmar. In addition to the main veins, there are many smaller sub-parallels to branching ore bearing veins. Economic ore minerals include sphalerite (ZnS), marmatite (ZnFeS), galena (PbS), chalcopyrite (CuFeS2) and tetrahedrite (CuFe12 Sb4S13). Gangue minerals include quartz (SiO2), pyrite (FeS2), magnetite (Fe2O4), pirrotite (Fe2+S), arsenopyrite (FeAsS) and fluorite (CaF2).

The Santa Barbara district has mineralization to indicate that it will continue to be a significant producer of lead, copper and zinc for decades. The full potential of the district has not yet been defined, but the area seems to justify an increase in exploration.

Santa Barbara includes three main underground mines (San Diego, Segovedad and Tecolotes). The mining operations at Santa Barbara are more diverse and complex than any of the other mines in Companys Mexican operations, with veins that aggregate approximately 21 kilometers in length.

Due to the variable characteristics of the ore bodies, four types of mining methods are used: shrinkage stoping, long-hole drilled open stoping, cut-and-fill stoping and horizontal bench stoping.

The concentrator plant has a milling capacity of 5,800 tons of ore per day and includes the following equipment:
• Six primary jaw crushers,
• one secondary crusher,
• two tertiary crushers,
• three mills, and
• three flotation circuits.

The ore, once crushed, is processed in the flotation plant to produce concentrates. The flotation plant has a capacity of 5,800 tons of ore per day. The lead concentrate produced is treated at a third party refinery in Mexico. The copper concentrates are treated at our La Caridad smelter and the zinc concentrates are either treated at the San Luis Potosi zinc refinery or exported.